B4-002 Autonomic Nervous System Flashcards
mediates adaptive behavioral and physiological effects in response to variety of internal and external sensory stimuli
ANS
have a final interneuronal synapse between a CNS (preganglionic) neuron and a peripheral (postganglionic) neuron
autonomic motor pathways
- don’t have neurons in ganglia
- CNS neuron project directly into muscle
voluntary motor pathways
have ganglia which contain peripheral neurons but not interneuronal synapses
sensory nerves
both sympathetic and parasympathetic ganglia have
cholinergic excitatory synapses
ganglionic neurotransmission in both sympathetic and parasympathetic pathways is mediated by
excitatory nicotinic cholinergic receptors
output is discrete
parasympathetic nervous system
output is diffuse
sympathetic nervous system
sites of autonomic neurotransmission
varicosities
transmission between a varicosity and target cell occurs across a
junction
prejunctional component
varicosity
postjunctional component
target cell
primary transmitters of parasympathetic neuroeffector transmission
- acetylcholine
- nitric oxide
acetylcholine: synthetic enzyme
choline acetyltransferase
nitric oxide: synthetic enzyme
NO synthase
acetylcholine: termination
cholinesterase
nitric oxide: termination
diffusion
acetylcholine: receptor
muscarinic
nitric oxide: receptor
guanylate cyclase
acetylcholine: positively effects
parasympathetic
M1, M3, M5
acetylcholine: negatively effects
parasympathetic
M2, M4
nitric oxide: effect
smooth muscle relaxation
sympathetic neurotransmitters
acetylcholine (5%)
norepinephrine
acetylcholine: effects
sympathetic
- eccrine sweat glands
- gland excitation
- thermoregulation only
norepinephrine: synthetic enzyme
dopamine B-hydroxylase
norepinephrine: termination
- 80% reuptake
- COMT, MAO
`
norepinephrine: receptor
adrenoreceptor
a1 is located
post junctional
a1 causes
- smooth muscle to contract
- increased salivation
a2 is located
pre-junctional
a2 inhibits
NE release
b1 is located in
heart, kidneys
b1 causes
- increased inotropy
- increased chronotropy
- increased angiotensin II
b2 is located
- smooth muscle
- glands
b2 causes
- smooth muscle relaxation
- increased salivation
- increased glycogenolysis
B3 is located
fat
B3 causes
increased lipolysis
acetylcholine and norepinephrine can excite or inhibit depending on
types of post junctional receptors present on target cell
the amount of transmitter released by postjunctional autonomic nerves is regulated by
prejunctional inhibitory autoreceptors
if excitatory transmitter release is persistently high…
post junctional receptor sensitivity can decrease
if excitatory transmitter release is continuously low…
receptor sensitivity can increase
mediates “fight or flight”
sympatho-adrenal system
characterized by broad and diffuse system activation
sympathetic system
mediates “feed and breed”
parasympthetic system
characterized by discrete changes in activity to selected organs
parasympathetic system
the parasympathetic system activates non vascular smooth muscle via
cholinergic receptors
the parasympathetic system always relaxes spinchters via
cholinergic receptors
the parasympathetic system inhibits cardiac activity via
cholinergic receptors
the parasympathetic system activates glands via
cholinergic receptors
the parasympathetic system relaxes vascular smooth muscle via
nitrergic receptors
the sympathetic system contracts smooth muscles via
a1 receptors
the sympathetic system relaxes smooth muscle via
b2 receptors
the sympathetic system excites the heart and kidney JG cells via
b1 receptors
the sympathetic system excites adipocytes via
b3 receptors
the sympathetic system increases glandular secretion via
a1, b2, M
[sympathetic or parasympathetic]
mydriasis
pupil dialtion
sympathetic
[sympathetic or parasympathetic]
miosis
pupil constriction
parasympathetic
- occurs when sympathetic innervation to the head is damaged
- ptosis
- miosis
- facial anhidrosis and flushing
horner’s syndrome
[sympathetic or parasympathetic]
increases GI motility
parasympathetic
[sympathetic or parasympathetic]
decreases spinchter tone
parasympathetic
[sympathetic or parasympathetic]
increases enteric blood flow
parasympathetic
[sympathetic or parasympathetic]
reduces GI motility
sympathetic
[sympathetic or parasympathetic]
increases spinchter tone
sympathetic
too little sympathetic NE in the bladder will cause
incontinence
too little parasympathetic ACh in the bladder will cause
retention
sacral parasympathetic neuropathy can cause
erectile dysfunction
NO acts on gaunylate cyclase to produce
cGMP
causes smooth muscle relaxation and vasodilation
NO acts on gaunylate cyclase to produce
cGMP
causes smooth muscle relaxation and vasodilation
Viagra inhibits phosphodiesterase 5, which breaks down cGMP.
This amplifies
the affect of NO, increasing tumescence
name the receptor type and state if sympathetic or parasympathetic
protect retina:
* pupillary constrictor
* cleanse lacrimal
M+
parasympathetic
name the receptor type and state if sympathetic or parasympathetic
protect from noxious agents
* bronchiolar smooth muscle
* nasopharyngeal glands
M+
parasympathetic
name the receptor type and state if sympathetic or parasympathetic
decrease heart rate
M-
parasympathetic
name the receptor type and state if sympathetic or parasympathetic
promote digestion:
* salivary gland secretion
* enteric smooth muscle
M+
parasympathetic
name the receptor type and state if sympathetic or parasympathetic
increased blood flow to vascular smooth muscle
NO-
parasympathetic
name the receptor type and state if sympathetic or parasympathetic
defecation:
anal spinchter SM
M-
parasympathetic
name the receptor type and state if sympathetic or parasympathetic
urination:
bladder SM
M+
parasympathetic
name the receptor type and state if sympathetic or parasympathetic
urinary:
relax GU spinchters
M-
parasympathetic
name the receptor type and state if sympathetic or parasympathetic
erection
NO-
parasympathetic
name the receptor type and state if sympathetic or parasympathetic
increased light, distance vision:
* pupillary dilator
* tarsal SM
a1+
sympathetic
name the receptor type and state if sympathetic or parasympathetic
increased air intake:
bronchiolar SM
b2-
sympathetic
name the receptor type and state if sympathetic or parasympathetic
delay digestion:
enteric smooth muscle
b2-
sympathetic
name the receptor type and state if sympathetic or parasympathetic
delay digestion:
decreased blood flow to GI
a1+
sympathetic
name the receptor type and state if sympathetic or parasympathetic
delay defecation:
anal spinchter SM
a1+
sympathetic
name the receptor type and state if sympathetic or parasympathetic
thick, copius saliva
a1, B2+
sympathetic
name the receptor type and state if sympathetic or parasympathetic
increased blood glucose from liver
B2
sympathetic
name the receptor type and state if sympathetic or parasympathetic
increase heart rate
b1+
sympathetic
name the receptor type and state if sympathetic or parasympathetic
prevent urination:
bladder body SM
b2-
sympathetic
name the receptor type and state if sympathetic or parasympathetic
prevent urination:
GU spinchters
a1+
name the receptor type and state if sympathetic or parasympathetic
ejaculation
a1+
sympathetic
name the receptor type and state if sympathetic or parasympathetic
hair follicle smooth muscle
a1+
sympathetic
name the receptor type and state if sympathetic or parasympathetic
eccrine sweat glands
M+
sympathetic
name the receptor type and state if sympathetic or parasympathetic
apocrine sweat glands
a1+
sympathetic
name the receptor type and state if sympathetic or parasympathetic
lipolysis
b3+
sympathetic
name the receptor type and state if sympathetic or parasympathetic
increased force of skeletal muscle
b2+
sympathetic
name the receptor type and state if sympathetic or parasympathetic
skeletal VSM
b2-
sympathetic
name the receptor type and state if sympathetic or parasympathetic
cutaneous, splanchic, renal VSM
a1+
sympathetic
dry mouth is caused by
xerostomia
reduced SNS/PSNS excitatory innervation
dsyphagia is caused by
reduced PSNS-mediated motility
airway obstruction is caused by
PSnS constriction accompanying loss of SNS dilation
SNS loss causes what change in heart rate?
bradycardia
PSNS loss causes what change in heart rate?
tachycardia
PSNS loss causes what GI disturbances?
- hypomobility
- constipation
SNS loss causes what gastic distubances?
- hypermobility
- fecal incontinence
erectile dysfunction is caused by
PSNS loss
ejaculatory dysfunction is caused by loss of
SNS
urinary retention is caused by loss of
PSNS function
urinary incontinence is caused by loss of
SNS function
miosis is caused by loss of
SNS regulation
mydriasis is caused by loss of
PSNS function
anhydrosis is caused by loss of
SNS cholinergic function
pupillary dilation and urinary retention would be caused by a […] agonist
a1
reduced GI activity may be caused by a […] agonist
b2
increased heart rate may be caused by a […] agonist
b1
ganglionic neurotransmission is mediated by
excitatory nicotinic receptors
blocking ganglionic neurotransmission leads to
- less Ach and NE released
- decreased plasma epinephrine
what type of drug
- excitatory to smooth muscle
- inhibit spinchter contraction
- activate sweat glands
- constrict pupils
- decrease heart rate
muscarinic agonist
what type of drug would:
- cause tachycardia
- no change in blood pressure
beta 1 agonist
mucarinic effects
Diarrhea
Urination
Miosis
Bronchospasm
Bradycardia
Eemesis
Larcrimation
Sweating
Salivation
